1. Field of the Invention
The present invention relates to a semiconductor light-emitting device, and particularly to a II-VI compound semiconductor light-emitting device which emits lights from green to blue colors.
2. Description of the Related Art
Recently, study and development to improve the property of a semiconductor laser using a strained quantum well have become brisk. As the semiconductor laser using the strained quantum well, there are developed a III-V system semiconductor laser or an AlGaInP system semiconductor laser emitting a light with a wavelength of 600 nm band, an InGaAsP system semiconductor laser emitting a light with a wavelength of 1 .mu.m band, an InGaAsP system semiconductor laser emitting a light with a wavelength of 1.3 to 1.5 .mu.m band, and so on.
The strained quantum well has two kinds of type, one of which is of a strain caused by compression and the other of which is of strain caused by tension. In general, the strained quantum well is gripped by barrier layers of lattice matching system.
As disclosed in Patent Application laid open Ser. No. 8-18161, since a II-VI family compound semiconductor light-emitting device having an active region of quantum well structure has an active region of a quantum well structure by at least one quantum well layer having a compressive strain relative to a substrate and made of ZnCdSSe and at least one barrier layer having a tensile strain relative to a substrate and made of ZnSSe, the breeding speed of crystal defect is suppressed, the life time of the device may be extended, and further the thickness of strained quantum well layer is made thick sufficiently without being restricted by the critical film thickness of the strained quantum well layer, whereby a II-VI compound semiconductor light-emitting device, which can confine the light sufficiently and is high in reliability, is proposed.